where \(k_r\)  and \(k_{\psi }\)  refer to the order of derivative of the coordinate \(r\)  and yaw angle \(\psi \) , respectively. For the minimum-snap cost in [1]}, \(k_r=4\)  and \(k_{\psi }=2\)  are used.
The constraints include convex set \(\mathcal {C}_i \subseteq \mathbb {R}^3\)  of adjustable waypoints at time instances, i.e.,
\(r_1(t_{0}) \in \mathcal {C}_0, \ r_i(t_i) \in \mathcal {C}_i, \ i \in \lbrace 1,2,\dots ,m\rbrace .\) 
